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15 * If applicable, add the following below this CDDL HEADER, with the
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27 #pragma ident "%Z%%M% %I% %E% SMI"
31 * Positive test for ring buffer policy.
33 * SECTION: Buffers and Buffering/ring Policy;
34 * Buffers and Buffering/Buffer Sizes;
35 * Options and Tunables/bufsize;
36 * Options and Tunables/bufpolicy
40 * We make some regrettable assumptions about the implementation in this test.
41 * First, we assume that each entry for the printf() of an int takes _exactly_
42 * eight bytes (four bytes for the EPID, four bytes for the payload). Second,
43 * we assume that by allocating storage for n + 1 records, we will get exactly
44 * n. Here is why: the final predicate that evaluates to false will reserve
45 * space that it won't use. This act of reservation will advance the wrapped
46 * offset. That record won't be subsequently used, but the wrapped offset has
47 * advanced. (And in this case, that old record is clobbered by the exit()
48 * anyway.) Thirdly: we rely on t_cpu/cpu_id. Finally: we rely on being
49 * able to run on the CPU that we first ran on.
51 #pragma D option bufpolicy=ring
52 #pragma D option bufsize=40
53 #pragma D option quiet
65 cpuid = curthread->t_cpu->cpu_id;
69 /curthread->t_cpu->cpu_id == cpuid && n < 100/